Current technology of switching is optical-electronic-optical, i.e., optical signals are converted to electrical ones that drive lasers down the fiber to which the signal needs to be switched to. This method has the following disadvantages:
Slow, due to the overhead associated with conversion to electrical and back to optical.
Expensive, due to the need for high speed switching electronics
Bulky. Compared to optical elements, these switches are orders of magnitude bulkier due to electronic systems that go along with them.
Wavelength-dependent operation.
Unlike electrical systems, the all-optical switching technology is still in its infancy and newer systems are being invented at a rapid pace. Currently all-optical switches are commercially available and have the following advantages over their electronic-based counterparts:
Fast, because the overhead of conversion to electrical and back to optical is eliminated.
Relatively inexpensive.
Small and compact.
The major disadvantage of many all-optical switches is operational dependence on the wavelength of light used. This is a source of concern in DWDM systems where signals “riding” on different wavelengths called carrier wavelengths need to be switched. Apart from the inherent advantages of all-optical switches, our technique has the advantage of being independent of wavelength. Some all-optical switches have losses due to reflection/refraction and are located external to the fiber.
These and other disadvantages of optical electrical optical and all optical switches are overcome by the invention as disclosed in a preferred embodiment.